Portion of a concrete anchor



FIG. 1 is a front perspective view of a portion of a concrete anchor showing my new design;

FIG. 2 is a top elevational view thereof; and,

FIG. 3 is a cross-sectional view thereof from the plane of the line 3—3 of FIG. 2.

The broken line representations of portions of the concrete anchor in FIGS. 1-3 are shown for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a portion of a concrete anchor, as shown and described. 